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Top 10 Reasons why your Basement is leaking in winter

Winters mean holidays and fun but it also comes with the problems of flooded basements. No one wants to ruin their holidays by mopping out the water from a flooded, leaky basement when you can easily enjoy with your family. It is general perception and basement flooding and leaks occur during the heavy rains but it is not so.

Leaking basements are very common during the winter due to a variety of reasons. Although there are many triggering conditions, the concluding factor is the moisture accumulation in your basement.

This accumulation of moisture can happen due to rains and also due to snow. Snow may seem harmless but comes with a lot of problems too. It is best to have your basement waterproofed so that you can enjoy your winters and don’t have to worry about any basement leaks or flooding of basements.

Here are the most common reasons due to which the waterproofing of your basement may fail during winters and you may be stuck with a leaky basement. It is best to be aware of these reasons beforehand and take precautionary measures to avoid leaky basements.

  1. Hydrostatic Pressure is the cause

We are aware of the gravitational pull of the earth, in the same way, the force exerted by a fluid due to the force of gravity is known as the Hydrostatic pressure.

It is one of the most common causes of leaky basements across the world. Your basement radiates heat during the winters which cause the frozen soil and snow to melt around the walls of your basement due to which trapped moisture gets accumulated around your basement. The hydrostatic pressure pushes down that trapped moisture.

The hydrostatic pressure can be very strong and it forces the moisture through the cracks and nooks of your foundation. It can also be so strong as to create cracks in the walls of your basement or your foundation so that the moisture gets a path to flow out. This is what causes the flooding of your basement during the winter.


  1. Radiation of Heat by Basements

While it is freezing outside and the whole neighbourhood is covered in a white sheet of snow, your basement is much warmer than the outside. Since your basement is below the ground level, it is insulated and is much warmer and cosier than outside. If your basement is unfinished, it will be less warm and if it is finished, it will be cosier.

But the soil and ground around and outside your basement is cold, frozen and covered in snow which causes a temperature difference between your basement and the outside world. As we all know, heat radiates from warmed to colder places, your basement walls radiate heat towards outside and the frozen snow and soil around your basement start melting.

It is common knowledge that basement walls radiate up to 8″.This causes the snow and soil to melt and the moisture starts accumulating. The basic cause of leaks is moisture and this moisture comes from the melting of snow by the heat radiation by your basement.

When this moisture finds no way out and is trapped between the soil and the walls of your basement, the problem starts and leaks might build up.

  1. Type of Soil

You may feel that the soil on which your house is standing is not important but it is not so. If the soil surrounding your basement is not the right type, you can expect a lot of leaks and flooding during the winter.

The soil plays a crucial role as the right type of soil helps in the proper drainage and irrigation of trapped moisture into the earth and does not let it leak into your basement.

The best type of soil is clay soil which helps in preventing any leaks because it absorbs the moisture trapped in the soil and expands due to which no hydrostatic pressure in-built near the basement walls thus avoiding any cracks and leaks.

If you do not have clay soil around your basement, it is recommended to have the area around your basement filled with clean fill dirt and topping it with stone. It will prevent any leaks, cracks in the foundation and walls and the stone will prevent erosion.


  1. Improper Drains and troughs

Properly designed, installed and functioning drains, troughs and eaves are very important for the proper drainage system of any household. These ensure that the water used in your house gets routed out in an efficient manner without creating any leaks and ultimately flooding.

But if these downspouts and troughs are not designed properly and are not functioning to their optimum level, they do more harm than good. When they function correctly, they work to get all the used water away from your house and avoid any leaks.

But if these drains, troughs, and eaves are not functioning properly or if they are not maintained properly, the water which was supposed to be carried away from your home, starts getting accumulated near your home and in turn your foundation. Once this water gets accumulated, hydrostatic pressures pull it down causing it to leak into your basement and start flooding it.

In order to ensure that no such thing happens, especially during the winters, it is recommended to properly maintain all your gutter and drains. Keep them clean and avoid any blockages. Also, ensure that the downspouts are at least 4 feet away from your foundation to maintain a safe distance.

  1. Cracks in the Basement floor

Although your basement may look fine and warm, the most common cause of leaks in the basement is the cracks in the basement floor and the walls. There are many causes of cracks in the basement like Storms, earthquakes, plumbing leaks, extreme heat, flooding etc.


While these causes may be beyond your control, but it important to identify these cracks in your basement and fix them properly. When the snow starts melting during the winters, it starts getting trapped in the soil around your basement walls and the foundation, causing the moisture to get trapped in and around your basement, it searches for every outlet it can get and the hydrostatic pressure starts building.

It causes the water to seep through the cracks in your basement floor and walls, resulting in a wet and flooded basement in the winters. If the cracks are not repaired or eliminated, the water will keep on seeping through them into your basement until the hydrostatic pressure is relieved.


  1. Improper Slope around your foundation

The slope of the soil surrounding your foundation should always slope away from your foundations. The minimum slope should be at least 6 inches facing away from your home. It may not seem like a big deal to you, but even this short slope helps in guiding all the flowing water away from your foundation, protecting it against the outer moisture.

If the slope is rounding or worse it is not there, it will cause the water to accumulate near your foundation and will cause frequent leaks into your basement. An improper slope will lead to improper drainage and will cause leaking of your basement.

The slope should always slope down at least 6 inches away from your foundation. Kindly ensure this while buying a house or ensure that a clear downwards path is created for the water to flow out and away from your foundation.

  1. Clogged Drains

While it may seem very simple that clogged drains will obviously lead to leaks but still it is one of the most common causes of leaks basements. People can simply avoid a lot of hassle of a flooded basement if they keep their drains unclogged and maintain them properly.

Clogged drains cause the water to go back up into your pipes and overflow your house and basement. The clogs can occur in any of the pipes in your homes or even the sewer line of your home or the main municipal sewer lines.

While you may be able to do anything for keeping the sewer lines from getting clogged, you can simply keep your drains clean and maintain them to keep them unclogged so that the water flows freely and avoid any flooding of your basement.


  1. Faulty Sump Pump

If your Sump Pump is faulty or not working properly it can cause flooding of your basement. A Sump Pump function is to collect the excess water in and around your basement and pump it out and away from your house. If your Sump Pump is faulty or not functioning, the water will accumulate in the sump pit and flood your basement very fast.

A Sump Pump is usually installed in one corner of your basement by creating a pit ( sump pit) in the floor of the basement where the water gets accumulated and when the pit is filled, the sump pump is activated and pumps out the water away from your basement and foundation.

There are a variety of reasons for faulty Sump Pumps like a failure of power, poop maintenance, improper installation or clogged drains. You should double-check your sump pump before the winter season arrives because it not checked and maintained, you will end up with a flooded basement in the middle of the holiday season.

  1. Leaky Basement Windows

While the windows in your basement allow the light to flow in your basement and make it bright, but leaky or open windows can allow the water to enter your basement as well. The basement windows should always be free of any cracks and properly sealed.

The areas around your basement windows which are known as window wells should have proper drainage system so that the water does not accumulate in the wells and seep in your basement but flow out of the wells properly. The leaks in the basement window wells are also one of the most common causes of basement leaks, so you should keep a close eye on them.

  1. Lateral Pressure

The lateral pressure is caused when the soil around your foundation and basement expands and increases the pressure against it. During normal weather, the water drains out of the soil but during winters, even the water in the soil is frozen, and when it starts melting, the soil absorbs more water, which leads to more expansion of the soil.


Detection of Leaks

Water tends to find the path of least resistance and will try to find every outlet to release the hydrostatic pressure which causes the basements prone to leaks and flooding. Sometimes, detecting a leak is very easy in your basement but sometimes it can be more subtle and you need to look for a few signs to know that your basement is having leaks before it is too late.

  1. Moulds
  2. Efflorescence
  3. Rotting Wood
  4. Rust Stains
  5. Drylock Flake
  6. Stained and wet floor
  7. Water Seepage
  8. Wall Cracks

These early warning signals will help you in detecting the leaks in your basement so that you can get them repaired in time and avoid the flooding of your basements.



The above the top ten reasons due to which the basement leaks are found and it can lead to serious flooding of the basement if not treated in time. As the winter season approaches, it is recommended you take precautionary measures well in advance and prepare well for the strong winters coming your way. You can get in touch with who are experts in this field.

You should always remember that if it is not raining, moisture is still present, in one form or the other. It can be in the form of hailstones, snow or rain. You should cross-check the 10 factors given above and ensure that none of these things is happening with your basement. It is much easier to stop a small leak or repair a crack which might only take an hour, against the pumping out a flooded basement which will not only waste your time but also money.

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